My first surprise on my 86GT. I guess I really didn't drive that far on the test drive to see if the radiator fan would run so guess what it doesn't. My understanding of the relay location is in front of the drivers headlight. Well from this thread and this image mine is not the same, I only have 4 wires.

https://www.fiero.nl/forum/Forum2/HTML/118126.html

Looking at the 86 service manual, the 4-wire fan relay used in V6 cars with the single speed fan, and 4 cylinder cars with the single speed fan. The 4 cylinder with air conditioning uses the 6-wire relay as pictured. The 4 wire relay has wire colors red, black/pink, brown/white, and dark green/white. BRN/WHT and DK GRN/WHT are the coil side, and RED and BLK/RED are the switch side with the fan motor.

I have A/C, I should have mentioned that.

Both V6's (AC and not) used the 4-wire relay in 86, just the 4 cylinder with AC (two-speed fan) had the 6-wire relay.

So with the relay connected and grounding the dark green/ white the fan should come on? Otherwise the relay would be bad if 12v is at the red wire which should be coming from the fuse.

You need 12V at the red wire and the brn/wht wire for the relay to work. Power at the red wire should be there at all times, but power at the brn/wht wire will only be present with the ignition switch in the RUN position. If the power circuits are good, then when you ground the grn/wht wire, you should get 12V at the black/red wire which should turn on the fan. If the fan still doesn't turn on, then check the fan's ground circuit to be sure it's not broken or corroded. Here's the circuit:

Thanks Bloozberry

Only 84 w/ AC uses Two speed rad fan.
85 and up uses Single speed setup w/ or w/o AC.

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The fan started so its probably the fan switch or connection issue. On my way out to check it out. I assume the fan switch is contacts and not a resistant type. Thanks bloozberry for the diagram. I will give you a point when I can.

Not sure which "fan switch" you're talking about. If you mean the one on the engine block, then it only completes the ground circuit when the water temperature is above 235 deg F. Even then, it grounds through the threads so if they're corroded or if someone used teflon tape on the threads, there's a good possibility it can't complete the ground path to the engine block. Also, if this is the switch you mean, if you ground it out it will run the fan continuously while the ignition is in run... not sure you want to do that. Perhaps wiring a temporary grounding switch on the dash would be a better idea.

Yes that's the one I am referring to, it's not grounding out so I grounded near the relay ( now runs cold). I did not but will try to ground the wire at the fan switch to verify its not the wire. I did try a resistance reading to ground but never closed. I am usually more thorough than I was today I just wanted to get it on the road for my first long drive.